Download Evolution, altruism and cognitive architecture: a critique of Sober

Biology and Philosophy (2006)
DOI 10.1007/s10539-006-9030-1
Ó Springer 2006
Evolution, altruism and cognitive architecture: a critique
of Sober and Wilson’s argument for psychological
altruism
STEPHEN STICH
Department of Philosophy & Center for Cognitive Science, Rutgers University, 26 Nichol Avenue,
New Brunswick, NJ 08901-2882, USA
(e-mail: [email protected]; phone: +732-932-9861; fax: +732-932-8617)
Received 3 August 2005; accepted in revised form 22 March 2006
Key words: Altruism, Cognitive architecture, Egoism, Evolution, Intrinsic and instrumental desire,
Natural selection, Sub-doxastic states
Abstract. Sober and Wilson have propose a cluster of arguments for the conclusion that
‘‘natural selection is unlikely to have given us purely egoistic motives’’ and thus that psychological altruism is true. I maintain that none of these arguments is convincing. However, the
most powerful of their arguments raises deep issues about what egoists and altruists are claiming
and about the assumptions they make concerning the cognitive architecture underlying human
motivation.
In their important book, Unto Others: The Evolution and Psychology of
Unselfish Behavior, Elliott Sober and David Sloan Wilson offer a new and
interesting evolutionary argument aimed at showing that in the venerable
dispute between psychological altruism and psychological egoism, altruism is
the likely winner. In this paper, I’ll argue that Sober and Wilson’s argument
relies on an implicit assumption about the cognitive architecture subserving
human action, that much recent work in cognitive science suggests the
assumption may be mistaken, and that without the assumption, their argument
is no longer persuasive. Before getting to any of that, however, we’ll need to fill
in a fair amount of background.
Preliminaries
Far too many discussions of evolution and altruism founder because they
fail to draw a clear distinction between two very different notions of
altruism which, following Sober and Wilson, I’ll call evolutionary altruism
and psychological altruism. One of the many virtues of Sober and Wilson’s
book is that they draw this distinction with exemplary clarity, and never
lose sight of it.
A behavior is evolutionarily altruistic if and only if it decreases the inclusive
fitness of the organism exhibiting the behavior and increases the inclusive fitness of some other organism. Roughly speaking, inclusive fitness is a measure of
how many copies of an organism’s genes will exist in subsequent generations.1
Since an organism’s close kin share many of its genes, an organism can increase
its inclusive fitness either by reproducing or by helping close kin to reproduce.
Thus many behaviors that help kin to reproduce are not evolutionarily altruistic, even if they are quite costly to the organism doing the helping.2
Evolutionary altruism poses a major puzzle for evolutionary theorists,
since if an organism’s evolutionarily altruistic behavior is heritable, we might
expect that natural selection would replace the genes that influence the
behavior with genes that did not foster altruistic behavior, and thus the
altruistic behavior would disappear. In recent years, there has been a great
deal of discussion of this problem. Some theorists, Sober and Wilson
prominent among them, have offered sophisticated models purporting to
show how, under appropriate circumstances, evolutionary altruism could
indeed evolve, while others have maintained that the evolution of altruism is
extremely unlikely, and that under closer examination all putative examples
of altruistic behavior will turn out not to be altruistic at all. In the memorable words of biologist Michael Ghiselin (1974, 247) ‘‘Scratch an ‘altruist’
and watch a ‘hypocrite’ bleed.’’ Since my focus, in this paper, is on psychological altruism, I’ll take no stand in the controversy over the existence of
evolutionary altruism.
A behavior is psychologically altruistic if and only if it is motivated by an
ultimate desire for the well-being of some other organism, and as a first pass,
we can say that a desire is ultimate if its object is desired for its own sake,
rather than because the agent thinks that satisfying the desire will lead to the
satisfaction of some other desire. Though I’ll need to say more about ultimate desires and psychological altruism, what’s already been said is enough
to make the point that evolutionary altruism and psychological altruism are
logically independent notions – neither one entails the other. It is logically
possible for an organism to be evolutionarily altruistic even though it has no
mind at all and thus can’t have any ultimate desires. Indeed, since biologists
interested in evolutionary altruism use the term ‘behavior’ very broadly, it is
possible for paramecia, or even plants, to exhibit evolutionarily altruistic
behavior. It is also logically possible for an organism to be a psychological
altruist without being an evolutionary altruist. For example, an organism
might have an ultimate desire for the welfare of its own offspring. Behaviors
resulting from that desire will be psychologically altruistic though not evolutionarily altruistic, since typically such behaviors will increase the inclusive
fitness of the parent.
1
Giving a more precise account would raise some of the deepest issues in the philosophy of
biology. (See, for example, Beatty 1992). Fortunately, for our purposes no more precise account
will be needed.
2
Some writers, including Sober & Wilson, define evolutionary altruism in terms of individual
fitness rather than inclusive fitness. I prefer the inclusive fitness account since, as we’ll soon see, it
makes it easier to understand how Sober & Wilson’s wise decision to focus on parental care
sidesteps the debate over the existence of evolutionary altruism.
I’ve said that to be psychologically altruistic, a behavior must be motivated
by an ultimate desire for the well-being of others. That formulation invites
questions about what it is for a behavior to be motivated by an ultimate desire
and about which desires are for the well-being of others. The second question,
though it certainly needs to be considered in any full dress discussion of psychological altruism, can be put-off to the side here, since a rough and ready
intuitive understanding of the notion is all I’ll need to explain Sober and
Wilson’s argument and my concerns about it.3 One interpretation of the traditional notion of practical reasoning provides a useful tool for explaining the
relevant sense of a behavior being motivated by an ultimate desire. On this
account, practical reasoning is a causal process via which a desire and a belief
give rise to or sustain another desire. That second desire can then join forces
with another belief to generate a third desire. And so on. Sometimes this
process will lead to a desire to perform what Goldman calls a ‘‘basic’’ action,
and that, in turn, will cause the agent to perform the basic action without the
intervention of any further desires.4 Desires produced by this process of
practical reasoning are instrumental desires – the agent has them because she
thinks that satisfying them will lead to something else that she desires. But not
all desires can be instrumental desires. If we are to avoid circularity or an
infinite regress there must be some desires that are not produced because the
agent thinks that satisfying them will facilitate satisfying some other desire.
These desires that are not produced or sustained by practical reasoning are the
agent’s ultimate desires. A behavior is motivated by a specific ultimate desire
when that desire is part of the practical reasoning process that leads to the
behavior. Figure 1 depicts some of these ideas in a format that will come in
handy later on.
If a behavior is produced by a process of practical reasoning that includes an
ultimate desire for the well-being of others, then that behavior is psychologically altruistic. Psychological egoism denies that there are any ultimate desires
of this sort; it maintains that all ultimate desires are self-interested. According
to one influential version of egoism, often called psychological hedonism, there
are only two sorts of ultimate desires: the desire for pleasure and the desire to
avoid pain. Another, less restrictive, version of egoism allows that people may
have a much wider range of ultimate self-interested desires, including desires
for their own survival, for wealth, for power and for prestige. Egoism
acknowledges that people sometimes have desires for the well-being of others,
but it insists that all these desires are instrumental. Psychological altruism, by
contrast, concedes that many ultimate desires are self-interested but insists that
there are also some ultimate desires for the well-being of others. Since psychological altruism maintains that people have both self-interested ultimate
desires and ultimate desires for the well-being of others, Sober and Wilson
sometimes refer to the view as motivational pluralism.
3
4
For some substantive discussion of the question see Stich et al. (in preparation).
For a classic statement of this account of practical reasoning, see Goldman (1970).
BELIEF 1
BELIEF 2
BELIEF 3
DESIRE 1
DESIRE 2
DESIRE 3
DESIRE 4
ACTION
INSTRUMENTAL
ULTIMATE
Figure 1. Practical reasoning, a causal process via which a desire and a belief give rise to or
sustain another desire. An ultimate desire is one which is not produced by practical reasoning.
Sober and Wilson’s evolutionary argument for psychological altruism
Sober and Wilson believe that there is an evolutionary argument for the
existence of the sort of motivational structures required for psychological
altruism. ‘‘Natural selection,’’ they maintain, ‘‘is unlikely to have given us
purely egoistic motives.’’5 While granting that their case is ‘‘provisional’’ (8),
they believe that their ‘‘analysis...provides evidence for the existence of psychological altruism’’ (12).
In setting out their argument, Sober and Wilson adopt the wise strategy
of focusing on the case of parental care. Since the behaviors that organisms
exhibit in taking care of their offspring are typically not altruistic in the evolutionary sense, we can simply put-off to the side whatever worries there may
be about the existence of evolutionary altruism. Given the importance of
parental care in many species, it is all but certain that natural selection played a
significant role in shaping that behavior. And while different species no doubt
utilize very different processes to generate and regulate parental care behavior,
it is plausible to suppose that in humans desires play an important role in that
process. Sober and Wilson believe that evolutionary considerations can help us
determine the nature of these desires. Here is how they make the point:
Although organisms take care of their young in many species, human
parents provide a great deal of help, for a very long time, to their children. We expect that when parental care evolves in a lineage, natural
selection is relevant to explaining why this transition occurs. Assuming
that human parents take care of their children because of the desires
they have, we also expect that evolutionary considerations will help
illuminate what the desires are that play this motivational role.’’ (301)
5
Sober and Wilson (1998), p. 12. Hereafter, all quotes from Sober and Wilson (1998) will be
identified by page numbers in parentheses.
Of course, as Sober and Wilson note, we hardly need evolutionary arguments
to tell us about the content of some of the desires that motivate parental care. But
it is much harder to determine whether these desires are instrumental or ultimate,
and it is here, they think, that evolutionary considerations can be of help.
We conjecture that human parents typically want their children to do
well – to live rather than die, to be healthy rather than sick, and so on.
The question we will address is whether this desire is merely an instrumental desire in the service of some egoistic ultimate goal, or part of a
pluralistic motivational system in which there is an ultimate altruistic
concern for the child’s welfare. We will argue that there are evolutionary
reasons to expect motivational pluralism to be the proximate mechanism for producing parental care in our species. (302)
Since parental care is essential in our species, and since providing it requires
that parents have the appropriate set of desires, the processes driving evolution
must have solved the problem of how to assure that parents would have the
requisite desires. There are, Sober and Wilson maintain, three kinds of solutions to this evolutionary problem.
A relatively direct solution to the design problem would be for parents
to be psychological altruists – let them care about the well-being of
their children as an end in itself. A more indirect solution would be for
parents to be psychological hedonists6 – let them care only about
attaining pleasure and avoiding pain, but let them be so constituted
that they feel good when their children do well and feel bad when their
children do ill. And of course, there is a pluralistic solution to consider
as well – let parents have altruistic and hedonistic motives, both of
which motivate them to take care of their children. (305)
‘‘Broadly speaking,’’ they continue, ‘‘there are three considerations that bear
on this question’’(305). The first of these is availability; for natural selection to
cause a trait to increase in frequency, the trait must have been available in an
ancestral population. The second is reliability. Since parents who fail to provide
care run a serious risk of never having grandchildren, we should expect that
natural selection will prefer a more reliable solution to a less reliable one. The
third consideration is energetic efficiency. Building and maintaining psychological mechanisms will inevitably require an investment of resources that might be
used for some other purpose. So, other things being equal, we should expect
natural selection to prefer the more efficient mechanism. There is, Sober and
Wilson maintain, no reason to think that a psychologically altruistic mechanism
6
Sober and Wilson cast their argument as contest between altruism and hedonism because ‘‘[b]y
pitting altruism against hedonism, we are asking the altruism hypothesis to reply to the version of
egoism that is most difficult to refute.’’(297)
would be less energetically efficient than a hedonist mechanism, nor is there any
reason to think that an altruistic mechanism would have been less likely to be
available. When it comes to reliability, on the other hand, they think there is a
clear difference between a psychologically altruistic mechanism and various
possible hedonistic mechanisms: an altruistic mechanism would be more reliable,
and thus it is more likely that the altruistic mechanism would be the one that evolved.
To make their case, Sober and Wilson offer a brief sketch of how hedonistic
and altruistic mechanisms might work, and then set out a variety of reasons for
thinking that the altruistic mechanism would be more reliable. However, it has
long been my conviction that in debates about psychological processes, the
devil is often in the details. So rather than relying on Sober and Wilson’s brief
sketches, I will offer somewhat more detailed accounts of the psychological
processes that might support psychologically altruistic and psychologically
egoistic parental behavior. After setting out these accounts, I’ll go on to
evaluate Sober and Wilson’s arguments about reliability.
Figure 2 is a depiction of the process underlying psychologically altruistic
behavior. In Figure 2, the fact that the agent’s child needs help (represented
by the unboxed token of ‘My child needs help’ in the upper left) leads to the
belief, My child needs help. Of course, formation of this belief requires
complex perceptual and cognitive processing, but since this part of the story
is irrelevant to the issue at hand, it has not been depicted. The belief, My
child needs help, along with other beliefs the agent has leads to a belief that a
certain action, A*, is the best way to help her child. Then, via practical
reasoning, this belief and the ultimate desire, I do what will be most helpful for
ALTRUISM
My child
needs help
My child
needs help
Other
Beliefs
A* is the best
way to help
my child
I do what will be
most helpful for
my child
I do A*
A*
Ultimate Desire
Instrumental Desire
Belief
Figure 2. The process underlying psychologically altruistic behavior.
Action
my child, leads to the desire to do A*. Since in this altruistic account the
desire, I do what will be most helpful for my child, is an ultimate desire, it is
not itself the result of practical reasoning. The hedonistic alternatives I’ll
propose retain all the basic structure depicted in Figure 2, but they depict the
desire that I do what will be most helpful for my child as an instrumental
rather than an ultimate desire.
The simplest way to do this is via what I’ll call Future Pain Hedonism, which
maintains that the agent believes she will feel bad in the future if she does not
help her child now. Figure 3 is my sketch of Future Pain Hedonism. In it, the
content of the agent’s ultimate desire is hedonistic: I maximize my pleasure and
minimize my pain. The desire, I do what is most helpful for my child, is an
instrumental desire, generated via practical reasoning from the ultimate
hedonistic desire along with the belief that If I don’t do what is most helpful for
my child I will feel bad.
Figure 4 depicts another, more complicated, way in which the desire, I do
what is most helpful to my child, might be the product of hedonistic practical
reasoning, which I’ll call Current Pain Hedonism. On this account, the child’s
need for help causes the parent to feel bad, and the parent believes that if she
feels bad because her child needs help and she does what is most helpful, she
will stop feeling bad. This version of hedonism is more complex than the
previous version, since it includes an affective state – feeling bad – in addition
to various beliefs and desires, and in order for that affective state to influence
practical reasoning, the parent must not only experience it, but know (or at
least believe) that she is experiencing it, and why.
Future Pain
Hedonism
My child
needs help
If I don’t do
what will be
most helpful
for my child, I
will feel bad
I maximize my
pleasure &
minimize my pain
My child
needs help
Other
Beliefs
A* is the best
way to help
my child
I do what will be
most helpful for
my child
I do A*
A*
Ultimate Desire
Instrumental Desire
Figure 3. The process underlying future pain hedonism.
Belief
Action
My child
needs help
If I feel bad b/c
my child needs
help, then if I do
what is most
helpful for my
child, I will stop
feeling bad
I maximize my
pleasure &
minimize my pain
My child
needs help
If I do what is
most helpful for
my child, I will
stop feeling bad
Other
Beliefs
I feel bad b/c
my child needs
help
I feel bad b/c my child needs help
Current Pain
Hedonism
A* is the best
way to help
my child
I do what will be
most helpful for
my child
I do A*
A*
Ultimate Desire
Instrumental Desire
Belief
Action
Affective State
Figure 4. The process underlying current pain hedonism.
In their attempt to show that natural selection would favor an altruistic
process over the hedonistic alternatives, Sober and Wilson offer a number of
arguments, all of them focused on the more complicated Current Pain Hedonism, though they think that ‘‘the argument would remain the same if we
thought of the hedonist as acting to avoid future pain’’ (318). In discussing
these arguments, I’ll start with three that I don’t find very plausible; I’ll then
take up one that I think poses a serious challenge to hedonism and leads to
some important questions about how, exactly, psychological egoism and psychological altruism should be understood.
A first pair of arguments both focuses on the causal link between believing
that one’s child needs help and feeling an appropriate level of distress or pain.
The worry raised by the first argument is that the link could occasionally fail.
If the fitness of hedonism depends on how well correlated the organism’s pleasure and pain are with its beliefs about the well-being of its
children, how strong is this correlation apt to be? (315)...[W]e think it
is quite improbable that the psychological pain that hedonism postulates will be perfectly correlated with believing that one’s children are
doing badly. One virtue of ALT [altruism] is that its reliability does
not depend on the strength of such correlations.’’ (316, emphasis in the
original)
The second argument focuses on the fact that, to do its job appropriately, the
mechanism underlying the belief-to-affect link must not only produce pain or
distress, it must produce lots of it.
Hedonism assumes that evolution produced organisms – ourselves
included – in which psychological pain is strongly correlated with
having beliefs of various kinds. In the context of our example of
parental care, the hedonist asserts that whenever the organism believes that its children are well off, it tends to experience pleasure;
whenever the organism believes that its children are doing badly, it
tends to feel pain. What is needed is not just that some pleasure and
some pain accompany these two beliefs. The amount of pleasure that
comes from seeing one’s children do well must exceed the amount
that comes from eating chocolate ice cream and from having one’s
temples massaged to the sound of murmuring voices. This may require some tricky engineering... To achieve simplicity at the level of
ultimate desires, complexity is required at the level of instrumental
desires. This complexity must be taken into account in assessing the
fitness of hedonism.7 (315)
Sober and Wilson are certainly right that current pain hedonism requires the
affect generated by the belief that one’s child is doing well or badly be of an
appropriate magnitude, and that this will require some psychological engineering that is not required by the altruist process. They are also right that the
mechanism responsible for this belief-to-affect link will not establish a perfect
correlation between belief and affect; like just about any psychological mechanism it is bound to fail now and then.
However, I don’t think that either of these facts offers much reason to think
that natural selection would favor the altruistic process. To see why, let’s first
consider the fact that the belief-to-affect link will be less than perfectly reliable.
It seems that natural selection has built lots of adaptively important processes
by using links between categories of belief and various sorts of affective states.
Emotions like anger, fear and disgust, which play a crucial role in regulating
behavior, are examples of states that are often triggered by different sorts of
beliefs. And in all of these cases, it seems (logically) possible to eliminate the
pathway that runs via affect, and replace it with an ultimate desire to behave
appropriately when one acquires a triggering belief. Fear, for example, might
be replaced by an ultimate desire to take protective action when you believe
7
It is perhaps worth noting that, pace Sober and Wilson, neither of these arguments applies to
Future Pain Hedonism, since that version of hedonism does not posit the sort of belief-to-affect
link that Sober and Wilson are worried about. I should also note that, for simplicity, in discussing
these arguments I’ll ignore the pleasure engendered by the belief that one’s child is well off and
focus on the pain or distress engendered by the belief that one’s child is doing badly.
that you are in danger. Since natural selection has clearly opted for an emotion
mediation system in these cases rather than relying on an ultimate desire that
avoids the need for a belief-to-affect link, we need some further argument to
show that natural selection would not do the same in the case of parental care,
and Sober and Wilson do not offer one.
The second argument faces a very similar challenge. It will indeed require some
‘‘tricky engineering’’ to be sure that beliefs about one’s children produce the right
amount of affect. But much the same is true in the case of other systems involving
affect. For the fear system to work properly, seeing a tiger on the path in front of
you must generate quite intense fear – a lot more than would be generated by
your belief that if you run away quickly you might stub your toe. While it no
doubt takes some tricky engineering to make this all work properly, natural
selection was up to the challenge. Sober and Wilson give us no reason to think
natural selection was not up to the challenge in the case of parental care as well.8
A third argument offered by Sober and Wilson is aimed at showing that
natural selection would likely have preferred a system for producing parental
care, which they call ‘PLUR’, in which both hedonistic motivation and altruistic motivation plays a role, over a ‘‘monistic’’ system that relies on hedonism
alone. The central idea is that, under many circumstances, two control
mechanisms are better than one.
PLUR postulates two pathways from the belief that one’s children
need help to the act of providing help. If these operate at least somewhat independently of each other, and each on its own raises the probability of helping, then the two together will raise the probability of
helping even more. Unless the two pathways postulated by PLUR
hopelessly confound each other, PLUR will be more reliable than
HED [hedonism]. PLUR is superior because it is a multiply connected
control device. (320, italics in the original)
Sober and Wilson go on to observe that ‘‘multiply connected control devices
have often evolved.’’ They sketch a few examples, then note that ‘‘further
examples could be supplied from biology, and also from engineering, where
intelligent designers supply machines (like the space shuttle) with backup
systems. Error is inevitable, but the chance of disastrous error can be minimized by well-crafted redundancy’’ (320).
Sober and Wilson are surely right that well-crafted redundancy will typically
improve reliability and reduce the chance of disastrous error. They are also
right that both natural selection and intelligent human designers have produced lots of systems with this sort of redundancy. But, as the disaster which
8
Edouard Machery has pointed out another problem with the ‘‘tricky engineering’’ argument.
On Sober and Wilson’s account, altruists will have many ultimate desires in addition to the desire to
do what will be most helpful for their children. So to insure that the desire leading to parental care
usually prevails will also require some tricky engineering.
befell the Columbia space shuttle vividly illustrates, human engineers also often
design crucial systems without backups. So too does natural selection, as people
with damaged hearts or livers, or with small but disabling strokes, are all too
well aware. One reason for lack of redundancy is that redundancy almost never
comes without costs, and those costs have to be weighted against the incremental benefits that a backup system provides. Since Sober and Wilson offer us
no reason to believe that, in the case of parental care, the added reliability of
PLUR would justify the additional costs, their redundancy argument lends no
support to the claim that natural selection would prefer PLUR to a monistic
hedonism, or, for that matter, to a monistic altruism.
Sober and Wilson’s fourth argument raises what I think is a much more
troublesome issue for the hedonistic hypothesis.
Suppose a hedonistic organism believes on a given occasion that providing parental care is the way for it to attain its ultimate goal of maximizing pleasure and minimizing pain. What would happen if the
organism provides parental care, but then discovers that this action
fails to deliver maximal pleasure and minimal pain? If the organism is
able to learn from experience, it will probably be less inclined to take
care of its children on subsequent occasions. Instrumental desires tend
to diminish and disappear in the face of negative evidence of this sort.
This can make hedonistic motivation a rather poor control device.’’
(314) ...[The] instrumental desire will remain in place only if the organism ... is trapped by an unalterable illusion. (315)
Sober and Wilson are not as careful as they should be here. When it turns
out that parental care does not produce the expected hedonic benefits, the
hedonistic organism needs to have some beliefs about why this happened before
it can effectively adjust its beliefs and instrumental desires. If, for example, the
hedonist portrayed in Figures 3 or 4 comes to believe (perhaps correctly) that it
was mistaken in inferring that A* was the best way to help, then it will need to
adjust some of the beliefs that led to that inference, but the beliefs linking
helping to the reduction of negative affect will require no modification. But
despite this slip, I think that Sober and Wilson are onto something important
here. Both versions of hedonism that I’ve sketched rely quite crucially on
beliefs about the relation between helping behavior and affect. In the case of
Future Pain Hedonism, as elaborated in Figure 3, the crucial belief is: If I don’t
do what will be most helpful for my child, I will feel bad. In the version of
Current Pain Hedonism sketched in Figure 4, it’s: If I feel bad because my child
needs help, then if I do what is most helpful for my child, I will stop feeling bad.
These beliefs make empirical claims, and like other empirical beliefs they might
be undermined by evidence (including misleading evidence) or by more theoretical beliefs (rational or irrational) that a person could acquire by a variety of
routes. This makes the process underlying parental care look quite vulnerable
to disruption and suggests that natural selection would likely opt for some
more reliable way to get this crucial job done.9 The version of altruism depicted
in Figure 2 fits the bill nicely. By making the desire, I do what will be most
helpful for my child, an ultimate desire, it sidesteps the need for empirical beliefs
that might all too easily be undermined.
I think this is both a powerful argument for psychological altruism and an
original one, though ultimately I am not persuaded. To explain why, we’ll have
to clarify what the altruist and the egoist are claiming. Altruists, recall,
maintain that people have ultimate desires for the well-being of others, while
egoists believe that all desires for the well-being of others are instrumental, and
that all of our ultimate desires are self-interested. An instrumental desire is a
desire that is produced or sustained by a process of practical reasoning like the
one depicted in Figure 1 in which a desire and a belief give rise to or sustain
another desire. In the discussion of practical reasoning, in the ‘Preliminaries’
section, nothing was said about the notion of belief; it was simply taken for
granted. Like other writers in this area, including Sober and Wilson, I tacitly
adopted the standard view that beliefs are inferentially integrated representational states that play a characteristic role in an agent’s cognitive economy. To
say that a belief is inferentially integrated is to say (roughly) that it can be both
generated and removed by inferential processes that can take any (or just about
any) other beliefs as premises.
While inferentially integrated representational states play a central role in
many discussions of psychological processes and cognitive architecture, the
literature in both cognitive science and philosophy also often discusses belieflike states that are ‘‘stickier’’ than this. Once they are in place, these ‘‘stickier’’
belief-like states are harder to modify by acquiring or changing other beliefs.
They are also typically unavailable to introspective access. In Stich (1978), they
were dubbed sub-doxastic states. Perhaps the most familiar example of subdoxastic states are the grammatical rules that, according to Chomsky and his
followers, underlie speech production, comprehension and the production of
linguistic intuitions. These representational states are clearly not inferentially
integrated, since a speaker’s explicit beliefs about them typically has no effect
on them. A speaker can, for example, have thoroughly mistaken beliefs about
the rules that govern his linguistic processing without those beliefs having any
effect on the rules or on the linguistic processing that they subserve. Another
important example are the core beliefs posited by the psychologists Susan
Carey and Elizabeth Spelke (Carey and Spelke 1996; Spelke 2000, 2003). These
9
Note that the vulnerability to disruption we’re considering now is likely to be a much more
serious problem than the vulnerability that was center stage in Sober and Wilson’s first argument.
In that argument, the danger posed for the hedonistic parental care system was that ‘‘the psychological pain that hedonism postulates’’ might not be ‘‘perfectly correlated with believing that
one’s children are doing badly’’ (316, emphasis in the original). But, absent other problems, a
hedonistic system in which belief and affect were highly – though imperfectly – correlated would
still do quite a good job of parental care. Our current concern is with the stability of the crucial
belief linking helping behavior and affect. If that belief is removed the hedonistic parental care
system simply crashes, and the organism will not engage in parental care at all, except by accident.
are innate representational states that underlie young children’s inferences
about the physical and mathematical properties of objects. In the course of
development, many people acquire more sophisticated theories about these
matters, some of which are incompatible with the innate core beliefs. But, if
Carey and Spelke are correct, the core beliefs remain unaltered by these new
beliefs and continue to affect people’s performance in a variety of experimental
tasks. Although sub-doxastic states are sticky and hard to remove, they do play
a role in inference-like interactions with other representational states, though
their access to other representational premises and other premises’ access to
them is limited. In The Modularity of Mind, Fodor (1983) notes that representational states stored in the sorts of mental modules he posits are typically
sub-doxastic, since modules are ‘‘informationally encapsulated’’. But not all
sub-doxastic states need reside in Fodorian modules.
Since sub-doxastic states can play a role in inference-like interactions, and
since practical reasoning is an inference-like interaction, it is possible that subdoxastic states play the belief-role in some instances of practical reasoning. So,
for example, rather than the practical reasoning structure illustrated in Figure 1, some examples of practical reasoning might have the structure shown in
Figure 5. What makes practical reasoning structures like this important for our
purposes is that, since SUB-DOXASTIC STATE 1 is difficult or impossible to
remove using evidence or inference, DESIRE 2 will be reliably correlated with
DESIRE 1.
Let’s now ask whether, in Figure 5, DESIRE 2 is instrumental or ultimate?
As we noted earlier, the objects of ultimate desires are typically characterized
as ‘‘desired for their own sakes’’ while instrumental desires are those that
agents have only because they think that satisfying the desire will lead to the
satisfaction of some other desire. In Figure 5, the agent has DESIRE 2 only
because he thinks that satisfying the desire will lead to the satisfaction of
DESIRE 1. So it looks like the natural answer to our question is that DESIRE 2 is instrumental; the only ultimate desire depicted in Figure 5 is
DESIRE 1.
If this is right, if desires like DESIRE 2 are instrumental rather than ultimate, then Sober and Wilson’s evolutionary argument for psychological
altruism is in trouble. The central insight of that argument was that both
SUB-DOXASTIC
STATE 1
DESIRE 1
BELIEF 2
BELIEF 3
DESIRE 2
DESIRE 3
DESIRE 4
ACTION
Figure 5. An episode of practical reasoning in which a sub-doxastic state plays a role.
versions of hedonism rely on empirical beliefs which might all too easily be
undermined by other beliefs the agent might acquire. Suppose, however, that in
Figures 3 and 4, the representations
If I don’t do what will be most helpful for my child, I will feel bad
and
If I feel bad because my child needs help, then if I do what is most helpful for my child, I will stop feeling bad
are not beliefs but sticky sub-doxastic states. If we grant that desires produced
or sustained by a desire and a sub-doxastic state count as instrumental desires,
not ultimate desires, then the crucial desire whose presence Sober and Wilson
sought to guarantee by making it an ultimate desire, viz.
I do what will be most helpful for my child
is no longer at risk of being undermined by other beliefs. Since the crucial
desire is reliably present in both the Altruistic model and in both versions of the
Hedonist model, natural selection can’t prefer Altruism because of its greater
reliability in getting a crucial job done.
In a passage from Sober and Wilson quoted earlier, they noted that when an
instrumental desire does not lead to the expected hedonic pay-off, the ‘‘desire
will remain in place only if the organism ... is trapped by an unalterable illusion’’ (315). But as a number of authors have noted, some illusions – or as I
would prefer to put it, some belief-like representational states that are not
strictly true – are conducive to fitness (Stich 1990; Plantinga 1993; Sober 1994;
Godfrey-Smith 1996). In a variety of domains, it appears that natural selection
has used sub-doxastic states and processes that have some of the features of
mental modules to insure that those representations stay put and are not
undermined by the systems that revise beliefs. Since natural selection often
exploits the same trick over and over again, it is entirely possible that, when
faced with the problem of assuring that parents were motivated to care for their
children, this was the strategy it selected. My conclusion, of course, is not that
parental care is subserved by an egoistic psychological process, but rather that
Sober and Wilson’s argument leaves this option quite open. Their analysis does
not ‘‘provide... evidence for the existence of psychological altruism’’ (12).
Acknowledgements
I’m grateful to Elliott Sober, Edouard Machery, Kim Sterelny and an anonymous referee for helpful comments on earlier drafts of this paper.
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